Most learned Lutherans raised on Lutheran lore are eminently familiar with a different set of Martin Luther's requirements for being a theologian: oratio, meditatio, tentatio faciunt theologum (= prayer, meditation, and temptation make the theologian).
But Luther was fond of lists, and frequently developed parallel lists for the same topic. In his writings you'll find there are 2--no, 3--take that back, 7! marks of the church. Likewise, the fuller list of the "things that make the theologian" can be expanded to six items: 1. the grace of the Spirit; 2. temptation; 3. experience [just as no one can understand Vergil's Georgics, according to some of Luther's last words, without having been a farmer for five years; and just as no one can think about ethics, according to Aristotle (Eth. Nic. 1.4), without having been raised and become practiced in virtuous habits; so also the real theologian can't really understand this or that Word of God and its claims on him apart from a life lived under the horrifying Law and the sweetness of the Gospel]; 4. the occasion; 5. unstinting reading; 6. knowledge of the "good arts."
It falls to Lutheran higher education, with its purpose through intellective means to produce theologically learned and eloquent laity and clergy, to provide 5. and 6. Do we seek a rationale, a historical grounding, in the Wittenberg Reformation for present-day endeavors in Lutheran higher education? Here it is, in nuce: bonarum artium cognitio, knowledge of the "good arts" (one of a number of monikers in the Good Doctor's contemps for "the liberal arts," including: bonae litterae, litterae humaniores, artes liberales) gained through a sedula lectio, an unstinting reading. In other words: immersion in the liberal arts. Anything else is a mere distraction.
This is hardly an antiquated idea. To be sure, it is antique, and hails from antiquity. But in a time much like our own, when things were changing more quickly than you could bat an eye (printing press ~ internet; space exploration ~ discovery of the New World; engagement with "the Turk" ~ engagement with the modern Islamic world; social upheaval ~ well, social upheaval), it was precisely to the ages-old disciplines of the liberal arts that the Reformers turned to anchor their intellectual world. Because, as they well knew, nihil sub sole novum: there is, in fact, nothing new under the sun. Human nature hadn't changed; the way humans communicate hadn't really changed--they still used language, even if in print rather than solely in manuscripts, and certainly still in speech. And the way God addressed Himself to His creation hadn't changed: verbum Dei manet in aeternum, "the Word of God remains forever," acting toward His creation in the deeply "incarnational" way it has always acted--coming in human form, language, rhetoric, thought-patterns, etc., to address an audience that used the same to communicate.
The liberal arts were indispensable to the Reformation because, well, the Word is indispensable to the Reformation, and the Word cannot be understood externally, cannot be really grasped, without the external tools needed to understand it.
That's the Good Doctor on being a good doctor.